Increasing awareness of the benefits of tea drinking has spread through many societies, and has particularly been strong for individuals averse to consuming alcohol.
Whereas other hot drinks or foodstuffs using heated water, such as instant coffee granules, do not require boiled water, tea is superior when made with freshly boiled water.
Concurrently to this spread of tea-drinking there has been improvement in many societies of electrical provision, wherein to heat water for tea making it is currently quickest, easiest and most cost effective to heat and boil the water in an electrical kettle, according to quantities required.
Such kettles carry an indicator or gauge which shows the amount of water in the kettle, and a simple electrical element which heats up as electricity is passed through it.
However, even in current times of relative scarcity, frequently users will boil too much water, and will often boil the water again after initial boiling, in order to ensure freshly boiled water.